PRAGUE, Czech Republic -- After five blowout wins, the USA U19 World Championship Team (6-0) was tested by Serbia (5-1) Wednesday night in its final game of the second round and the U.S. made the plays required on the offensive and defensive ends to claim a hard-fought 71-62 victory.

Duke rising sophomore guard Rasheed Sulaimon scored a 15 points on 7-of-12 shooting. He grabbed five rebounds, four on the offensive end, and swiped three steals.

The win upped the USA’s record to 6-0 and clinched the important No. 1 seed for the medal quarterfinals round which begins Friday. The USA will face Group E No. 4 seed Canada (3-3) in a 2:15 p.m. (EDT) game on July 5 at the O2 Arena in Prague, Czech Republic. The contest will be streamed live by FIBA TV and ESPN3. Winners of the quarterfinal clashes will advance to the July 6 medal round semifinals and the championship’s finals are being held July 7.

“I think tomorrow we’ll just try and regroup a little bit. This was a real physical battle and game,” said USA and University of Florida head coach Billy Donovan. “So we’ll have to try and regroup and prepare to play Canada. They dealt with some injuries early on when the tournament started and they appear to be playing pretty well right now. They’re a talented team and we’ll need to come back and get rejuvenated.”

In a match-up of two undefeated teams, Serbia handled the USA’s pressure defense in the game’s early goings and with the USA trailing 9-8, the red, white and blue got scoring from four different players in an 11-2 run that lifted the U.S. to a 19-11 lead with 1:25 left in the quarter. Serbia tallied the final four points of the quarter and the U.S. led 19-15 after the first 10 minutes.

Ahead 25-21, four players again scored during a USA10-0 run that increased its lead to 35-21 with 55 seconds left before halftime. But again Siberia closed the stanza strong, this time with five straight points that left the score 35-26 at half.

Leading by as many as 12 points in the third period, the U.S. was unable to distance itself further as Serbia chipped the lead down to two points, 46-44, with 1:13 left in the third.

Center Jahlil Okafor (Whitney Young H.S./Chicago, Ill.) scored in the paint to make it 48-44, but Serbia’s Jovan Novak connected from beyond the 3-point line to make it a one-point game, 48-47. U.S. guard Nigel Williams-Goss (Findlay Prep/Happy Valley, Ore.) gave the USA some additional breathing room when he hit a short jumper off a drive with just 2 seconds left in the third quarter.

Taking a 50-47 advantage into the fourth, the U.S. was up 56-52 with 6:38 left in the game.

On his first and only 3-point attempt of the game, Rasheed Sulaimon (Duke University/Houston, Texas) hit nothing but net and 40 seconds later followed that up with a basket in the paint.

“Really coach called it,” Sulaimon said about his critical 3-pointer. “We’d been running a pin down on me the last couple of times on the offensive possessions and they were cheating so he just told me to fade and we executed it perfectly. Aaron Gordon made a great pass, Montrezl Harrell had a great screen and when the shot presented itself to me I just took it with confidence. It was a big time in the game and I’m just glad that it went in.”

After a defensive stop on the other end, Aaron Gordon (Archbishop Mitty H.S./San Jose, Calif.) scored off an offensive rebound to push the U.S. ahead 63-52 with 5:02 remaining and the USA went on to earn the 71-62 victory.

“I thought Rasheed (Sulaimon) put up a couple of big shots. He knocked down a three, had a chance for a three-point play in the lane, and we had a couple of offensive rebounds where we opened up the game from four right up to 11. Those were some big plays that Rasheed made,” said Donovan. “Really everybody contributed in one way or another. I thought our press was effective in the first half, we probably weren’t as effective in the second half as we needed to be but overall I think it was a game where we can learn a lot from the grind and the battle that went into it.”

Okafor headed the U.S. offensive effort with 16 points; Sulaimon finished with 15 points and five rebounds; Gordon collected 11 points and nine rebounds, six on the offensive end; and Montrezl Harrell (University of Louisville/Tarboro, N.C.) added nine points and seven rebounds.

“I love games when it’s very physical,” said Okafor, a 6’10 and 253-pound center who doesn’t turn 18 years old until Dec. 15. “The coaches told us earlier that this was the most physical team we would play so I was really ready for the game and it was a lot of fun.

“The coaches were telling our players to get me the ball and my teammates were trusting me to get a basket and so I was just trying to keep scoring for them and they kept trusting me and I just kept it going,” said Okafor, who scored six of his USA high 16 points in the third quarter.

The Americans were superior on the backboards, outrebounding Serbia 46 to 27, including 24 offensive boards. Serbia was forced into 18 turnovers and Serbia made just 41.2 percent of its shot attempts.